High-temperature $\eta$-pairing superconductivity in the photodoped Hubbard model

Lei Geng; Aaram J. Kim; Philipp Werner

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arXiv · 2602.17238

High-temperature $\eta$-pairing superconductivity in the photodoped Hubbard model

Lei Geng·Aaram J. Kim·Philipp Werner

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Abstract

We investigate superconductivity emerging in the photodoped Mott insulating Hubbard model using steady-state dynamical mean-field theory implemented on the real-frequency axis. By employing high-order strong-coupling impurity solvers, we obtain the nonequilibrium phase diagram for photoinduced $\eta$-pairing superconductivity with a remarkably high effective critical temperature. We further identify a superconducting gap in the momentum-resolved spectral function and optical conductivity, providing spectroscopic signatures accessible to experiments. Our results highlight a route to a controllable form of high-temperature superconductivity in nonequilibrium strongly correlated systems, fundamentally distinct from the equilibrium $s$-wave pairing state in the attractive Hubbard model or cuprate-like $d$-wave superconductors.

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Lei Geng, Aaram J. Kim, Philipp Werner. 2026-02-19. High-temperature $\eta$-pairing superconductivity in the photodoped Hubbard model. https://arxiv.org/abs/2602.17238

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